JP2017140804A - Liquid droplet discharge device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid droplet discharge device which can suppress deterioration of an infrared absorption agent in liquid to be supplied to a liquid droplet head in comparison with a case where liquid is stored without being cooled.SOLUTION: The liquid droplet discharge device comprises: a liquid droplet discharge head that discharges liquid droplets through a nozzle to form an image on a recording medium; storing means that stores liquid containing an infrared absorption agent; cooling means that cools the liquid stored in the storing means; heating means that heats liquid to be supplied from the storing means to the liquid droplet discharge head; supply means that supplies the heated liquid to the liquid droplet discharge head; and irradiating means that irradiates the image formed on the recording medium with laser light.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a droplet discharge device.

  Patent Document 1 discloses a colored ink container having a capacity V1 that contains a colored ink containing a solvent that polymerizes in the presence of an acid and a color component dispersed in the solvent, and a photoacid generator that generates an acid by light irradiation. Containing a reaction liquid in which an agent is added to a solvent and having a capacity V2 smaller than V1, a stirring container for mixing the colored ink and the reaction liquid to obtain a recording ink, and the colored ink A colored ink supply pump that supplies the colored ink from a container to the stirring container, a reaction liquid supply pump that supplies the reaction liquid from the reaction liquid container to the stirring container, and an inkjet that discharges the recording ink to a recording medium An inkjet recording apparatus comprising: a recording head; and a supply pipe for supplying the recording ink in the stirring container to the inkjet recording head. It is.

  Japanese Patent Application Laid-Open No. 2004-228688 includes an ink jet printer that has a recording head provided with nozzles that eject ink, and that forms an image by landing and curing the ink ejected from the nozzles on a recording medium. At least one of the first ink material and the second ink material; a first ink material supply unit that supplies the first ink material to the recording head; a second ink material supply unit that supplies the second ink material to the recording head; A supply amount adjusting device that adjusts the supply amount; and a control unit that controls the supply amount adjusting device based on a type of the recording medium, and mixing the first ink material and the second ink material, An ink jet printer characterized by constituting ink is disclosed.

JP 2011-073455 A JP 2004-195852 A

  An object of the present invention is to provide a droplet discharge device in which the deterioration of the infrared absorbent in the liquid supplied to the droplet discharge head is suppressed as compared with the case where the liquid is stored without being cooled. It is in.

  In order to achieve the above object, the invention described in claim 1 includes a droplet discharge head that discharges droplets from a nozzle to form an image on a recording medium, and a reservoir that stores a liquid containing an infrared absorber. Means, cooling means for cooling the liquid stored in the storage means, heating means for heating the liquid supplied from the storage means to the droplet discharge head, and the heated liquid to the droplet discharge head A droplet discharge device comprising: a supplying unit that supplies the laser beam; and an irradiation unit that irradiates the image formed on the recording medium with laser light.

  According to a second aspect of the present invention, there is provided a droplet discharge head that discharges droplets from a nozzle to form an image on a recording medium, a first storage unit that stores a liquid containing an infrared absorbent, and the first storage unit. A cooling unit that cools the liquid stored in one storage unit, and a second storage that stores a liquid that is smaller in volume than the first storage unit and that is supplied from the first storage unit to the droplet discharge head. Means, heating means for heating the liquid stored in the second storage means, supply means for supplying the heated liquid to the droplet discharge head, and the image formed on the recording medium. A droplet discharge device including irradiation means for irradiating laser light.

  The invention according to claim 3 is the droplet discharge device according to claim 1 or 2, wherein the cooling means cools the liquid to a temperature equal to or lower than a first temperature at which the infrared absorbent does not deteriorate.

  The invention according to claim 4 is the liquid droplet ejection apparatus according to any one of claims 1 to 3, wherein the cooling means cools the liquid to 10 ° C. or lower.

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the heating means heats the liquid to a temperature equal to or higher than a second temperature at which the liquid has a viscosity suitable for ejection. The droplet discharge device according to the item.

  A sixth aspect of the present invention is the droplet discharge apparatus according to any one of the first to fifth aspects, wherein the heating means heats the liquid to 30 ° C. or higher.

  According to a seventh aspect of the present invention, there is provided an acquisition means for acquiring the concentration of the infrared absorbent in the liquid discharged from the droplet discharge head, and a predetermined threshold value for the concentration of the infrared absorbent acquired by the acquisition means. Control means for controlling so that at least one of the cooling temperature of the liquid by the cooling means and the heating temperature of the liquid by the heating means is lowered when the temperature is less than It is a droplet discharge device according to any one of the above.

  The invention according to claim 8 is such that, when the concentration of the infrared absorbent acquired by the acquisition unit is less than a predetermined threshold, the control unit reduces the energy applied to the liquid by the heating unit. It is a droplet discharge device of Claim 7 controlled to.

  According to the first aspect of the present invention, as compared with the case where the liquid is stored without being cooled, the deterioration of the infrared absorbent in the liquid supplied to the droplet discharge head is suppressed.

  According to the second aspect of the present invention, the deterioration of the infrared absorbent in the liquid supplied to the droplet discharge head is suppressed as compared with the case where heating is performed without providing the second storage means.

  According to the invention described in claim 3, the stored liquid is cooled to a temperature at which the infrared absorbent is not deteriorated.

  According to invention of Claim 4, the liquid in storage is cooled to 10 degrees C or less.

  According to the fifth aspect of the present invention, the liquid before ejection is heated to a temperature at which the viscosity of the liquid becomes a viscosity suitable for ejection.

  According to the sixth aspect of the present invention, the liquid before discharge is heated to 30 ° C. or higher.

  According to the seventh aspect of the present invention, the concentration of the infrared absorbent in the liquid after ejection is maintained at a predetermined threshold value or more.

  According to the invention described in claim 8, the deterioration of the infrared absorber in the liquid generated during heating is reduced as compared with the case where the energy applied to the liquid is not changed.

1 is a schematic configuration diagram illustrating an example of a configuration of an ink jet recording apparatus according to an embodiment of the present invention. It is a schematic block diagram which shows an example of a structure of the ink supply apparatus which concerns on embodiment of this invention. 1 is a block diagram illustrating an example of an electrical configuration of an ink jet recording apparatus according to an embodiment of the present invention. It is a flowchart which shows an example of the process sequence of the "infrared absorber density | concentration adjustment process" performed by embodiment of this invention.

  Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings. In the present embodiment, an ink jet recording apparatus that forms an image on a recording medium by ejecting ink droplets will be described as an example of the liquid droplet ejecting apparatus of the present invention. The droplet discharge head is referred to as “inkjet recording head” or “recording head”. The liquid supply device is referred to as an “ink supply device”.

<Inkjet recording apparatus>
First, the ink jet recording apparatus according to this embodiment will be described. FIG. 1 is a schematic configuration diagram showing an example of the configuration of the ink jet recording apparatus according to the first embodiment of the present invention. As shown in FIG. 1, an inkjet recording apparatus 10 includes a recording head 12, a laser drying apparatus 14, an image temperature sensor 16, an image density sensor 18, a paper feed roll 20, a take-up roll 22, a transport roll 24, and an ink supply apparatus. 28 (only the container 30 is shown). For the ink supply device 28, refer to FIG. 2 and FIG.

  A long continuous paper P is wound around the paper feed roll 20 as a recording medium. The continuous paper P drawn from the paper supply roll 20 is conveyed in the direction of arrow A as the conveyance roll 24 rotates. The continuous paper P conveyed by the conveyance roll 24 is finally taken up by the rotation of the take-up roll 22. Hereinafter, the transport direction of the continuous paper P is simply referred to as “transport direction”. Between the paper feed roll 20 and the take-up roll 22, the recording head 12, the laser drying device 14, the image temperature sensor 16, and the image density sensor 18 are disposed so as to face the continuous paper P. . The laser drying device 14 is an example of “irradiation means”.

  In this embodiment, the recording head 12 is an inkjet recording head corresponding to each color of yellow (Y), magenta (M), cyan (C), and black (K) (hereinafter abbreviated as “recording head”). 12Y, 12M, 12C, and 12K. The recording heads 12Y, 12M, 12C, and 12K are arranged in the order described from the upstream side to the downstream side in the transport direction. Each of the recording heads 12Y, 12M, 12C, and 12K ejects ink droplets of a corresponding color from a plurality of nozzles to form an image of a corresponding color on the recording medium. The recording head 12 is driven by a known driving method such as a thermal method or a piezoelectric method. Further, when there is no need to distinguish each color of YMCK, they are collectively referred to as “recording head 12”.

  The laser drying device 14 is disposed on the downstream side in the transport direction with respect to the recording head 12. The laser drying device 14 includes a plurality of laser elements, and irradiates the continuous paper P on which the image is formed by the recording head 12 with laser light from the plurality of laser elements, thereby causing ink droplets of the image formed on the continuous paper P to be discharged. The image is fixed on the continuous paper P by drying.

  In the present embodiment, each YMCK color ink droplet contains an infrared absorber. When the continuous paper P on which an image is formed is irradiated with infrared laser light (hereinafter simply referred to as “laser light”), the infrared absorbing agent absorbs the laser light, thereby improving the absorption efficiency of the ink droplets with respect to the laser light. The temperature of the ink droplets is increased and dried. Here, “infrared light” is light having a longer wavelength than red light and having a long wavelength of about 700 nm or more.

  The image temperature sensor 16 is disposed on the downstream side in the transport direction with respect to the laser drying device 14. The image temperature sensor 16 is a sensor that detects the temperature of an image formed on the continuous paper P. Here, the “image temperature” is the temperature of the surface of the continuous paper P on which the image is formed, and is also the temperature of the ink droplets ejected onto the continuous paper P. The image temperature sensor 16 is preferably a non-contact type temperature sensor. For example, a radiation thermometer that measures the temperature of an object by measuring the intensity of infrared rays or the like emitted from the object to be measured is used.

  The image density sensor 18 is disposed on the downstream side in the transport direction with respect to the image temperature sensor 16. The image density sensor 18 is an optical reading device for detecting the density of an image formed on the continuous paper P. For example, a reflective optical sensor or the like that includes a light projecting unit and a light receiving unit, receives reflected light of light projected from the light projecting unit, and measures the intensity of the reflected light is used.

  In the ink jet recording apparatus, ink droplets are ejected by the recording head 12 onto the continuous paper P drawn from the paper supply roll 20 to form an image. The continuous paper P on which the image is formed by the recording head 12 is irradiated with laser light by the laser drying device 14 to dry the ink droplets of the image formed on the continuous paper P. Next, the image temperature sensor 16 detects the temperature of the image formed on the continuous paper P, and the image density sensor 18 detects the density of the image formed on the continuous paper P. Finally, the continuous paper P on which an image has been formed and dried is taken up by the take-up roll 22, and the image formation on the continuous paper P is completed.

  The inkjet recording apparatus 10 includes a container 30 that stores ink. In the present embodiment, containers 30Y, 30M, 30C, and 30K are provided corresponding to the recording heads 12Y, 12M, 12C, and 12K, respectively. Each of the containers 30 </ b> Y, 30 </ b> M, 30 </ b> C, and 30 </ b> K stores the corresponding color ink and supplies the ink stored in the corresponding recording head 12. Further, when there is no need to distinguish each color of YMCK, they are collectively referred to as “container 30”. Hereinafter, in order to distinguish from other containers, they are referred to as “first containers 30”. The first container 30 is an example of a “storage unit”.

  In the present embodiment, ink containing an infrared absorbent is stored in the first container 30 while being cooled by an ink supply device described below. Then, immediately before the supply to the recording head 12, the ink is heated, and the heated ink is supplied to the recording head 12. Infrared absorbers have poor storage stability and are particularly degraded in ink. By storing the ink containing the infrared absorbent while cooling, the deterioration of the infrared absorbent is suppressed as compared with the case where the ink is stored without being cooled and supplied to the recording head 12.

<Ink supply device>
Next, the ink supply device will be described. FIG. 2 is a schematic configuration diagram showing an example of the configuration of the ink supply apparatus according to the first embodiment of the present invention. As shown in FIG. 2, the ink supply device 28 includes a first container 30 that stores the ink 32 and a second container 50 that stores and heats the ink 32 supplied to the recording head 12. The second container 50 has a smaller volume than the first container 30. The first container 30 is an example of a “first storage unit”, and the second container 50 is an example of a “second storage unit”.

  One end of the supply pipe 60 is connected to the first container 30, and the other end is connected to the second container 50. The ink 32 in the first container 30 is supplied to the second container 50 through the supply pipe 60. The supply pipe 60 is provided with a first pump 62 that adjusts the supply amount of the ink 32.

  One end of the supply pipe 68 is connected to the second container 50, and the other end is connected to the recording head 12. The ink 32 in the second container 50 is supplied to the recording head 12 through the supply pipe 68. The supply pipe 68 is provided with a third pump 70 that adjusts the supply amount of the ink 32. The supply pipe 68 is an example of a “supply means”.

  The first container 30 that stores the ink 32 is provided with a first temperature sensor 34, a first temperature regulator 36, and a first liquid amount sensor 38. The first temperature sensor 34 detects the temperature of the ink 32 in the first container 30. The first temperature adjuster 36 adjusts the temperature of the ink 32 in the first container 30. The first liquid amount sensor 38 detects the liquid amount of the ink 32 in the first container 30. The first temperature regulator 36 is an example of a “cooling unit”.

  The second container 50 that stores and heats the ink 32 is provided with a second temperature sensor 53, a second temperature controller 54, a second liquid amount sensor 55, a viscometer 56, and a stirrer 58. The second temperature sensor 53 detects the temperature of the ink 32 in the second container 50. The second temperature adjuster 54 adjusts the temperature of the ink 32 in the second container 50. The second liquid amount sensor 55 detects the amount of ink 32 in the second container 50. The viscometer 56 measures the viscosity of the ink 32 in the second container 50. The stirrer 58 is rotationally driven by a motor to stir the ink 32 in the second container 50. The second temperature regulator 54 is an example of a “heating means”.

  The ink supply device 28 includes an ink supply device drive control unit 90 described later. Each part of the ink supply device 28 is driven and controlled by an ink supply device drive control unit 90 connected to a control unit 80 described later.

  In the ink supply device 28 described above, the temperature of the ink 32 in the first container 30 is the first temperature (for example, 10 ° C.) at which the infrared absorbent is not deteriorated by the first temperature sensor 34 and the first temperature adjuster 36. Adjusted to That is, the ink 32 in the first container 30 is cooled to suppress deterioration during storage. Next, the supply amount of the supply pipe 60 is adjusted by the first pump 62, and the supply amount of the supply pipe 68 is adjusted by the second pump 70. Then, the ink 32 in the first container 30 is supplied to the second container 50 with the adjusted supply amount.

  Next, the temperature of the ink 32 in the second container 50 is set to a viscosity suitable for ejection by the second temperature sensor 53 and the second temperature controller 54 (hereinafter referred to as “ejection viscosity”). Is adjusted to a second temperature (for example, 30 ° C.). That is, the ink 32 in the second container 50 is heated before being supplied to the recording head 12. By transferring the ink to the second container 50 having a volume smaller than that of the first container 30 and heating, the deterioration of the infrared absorbent is suppressed. The viscosity of the ink 32 is also reduced to the discharge viscosity by heating. Then, the supply amount of the supply pipe 68 is adjusted by the second pump 70, and the ink 32 in the second container 50 is supplied to the recording head 12 at a predetermined supply amount.

  A third temperature sensor 72 and a third temperature controller 74 are further provided in the supply pipe 68, and the temperature of the ink 32 passing through the supply pipe 68 is changed to the third temperature instead of the temperature of the ink 32 in the second container 50. You may adjust to 2nd temperature (for example, 30 degreeC) by the temperature sensor 72 and the 3rd temperature regulator 74. FIG. By heating the ink in the supply pipe 68 that is closer to the recording head 12 than the first container 30 and has a short residence time, the ink heating time is shortened. Moreover, a line mixer such as a static mixer may be inserted downstream of the third temperature controller 74 to promote stirring and mixing.

<Electrical configuration>
Next, the electrical configuration of the ink jet recording apparatus will be described.
FIG. 3 is a block diagram showing an example of the electrical configuration of the ink jet recording apparatus according to the first embodiment of the present invention. As shown in FIG. 3, the inkjet recording apparatus 10 includes a control unit 80 that is a computer that controls the entire apparatus and performs various calculations.

  That is, the control unit 80 includes a CPU 80A, a ROM 80B, a RAM 80C, a nonvolatile memory 80D, and an input / output interface (I / O) 80E. Each of the CPU 80A, ROM 80B, RAM 80C, memory 80D, and I / O 80E is connected to each other via a bus 80F. The CPU 80A reads various programs stored in the ROM 80B, and executes the programs using the RAM 80C as a work area.

  The I / O 80E of the control unit 80 includes a head drive unit 82, a laser drive unit 84, a conveyance drive unit 86, an image temperature sensor 16, an image density sensor 18, an operation display unit 87, a communication unit 88, and an ink supply device drive control. Unit 90 is connected.

  The head driving unit 82 drives the recording head 12 according to control information from the control unit 80. That is, the head driving unit 82 forms an image on the continuous paper P by ejecting ink droplets from the plurality of nozzles of the recording head 12 according to the ejection amount and ejection timing of the ink droplets for each of the plurality of nozzles. The laser driving unit 84 drives the laser drying device 14 according to control information from the control unit 80. That is, the laser driving unit 84 irradiates the continuous paper P on which the image is formed with the laser light from the plurality of laser elements of the laser drying device 14 according to the irradiation intensity and the turn-on / off timing for each of the plurality of laser elements. The transport driving unit 86 rotationally drives the plurality of transport rolls 24 in order to transport the continuous paper P according to control information from the control unit 80.

  The detection results of the image temperature sensor 16 and the image density sensor 18 are output to the control unit 80. The operation display unit 87 includes, for example, a display button, a touch panel display on which various information is displayed, and hardware keys such as a numeric keypad and a start button. With the above configuration, the operation display unit 87 receives instructions from the user and displays various information to the user. The communication unit 88 is a communication interface that is connected to a communication line (not shown) and transmits / receives communication data to / from an external device.

  The ink supply device drive control unit (hereinafter referred to as “drive control unit”) 90 is constituted by a computer including a CPU and the like. The drive control unit 90 controls driving of each unit of the ink supply device 28 in accordance with control information from the control unit 80. The drive controller 90 includes a first pump 62, a first temperature sensor 34, a first temperature regulator 36, a first liquid amount sensor 38, a stirrer 58, a second pump 70, a second temperature sensor 53, a second temperature. An adjuster 54, a second liquid amount sensor 55, a viscometer 56, a third temperature sensor 72, and a third temperature adjuster 74 are connected.

  The drive control unit 90 drives each of the first pump 62 and the second pump 70 according to the supply amount set by the control unit 80. The drive control unit 90 drives the stirrer 58 according to the stirring speed set by the control unit 80. In addition, each of the first temperature sensor 34, the first liquid amount sensor 38, the second temperature sensor 53, the second liquid amount sensor 55, the viscometer 56, the third temperature sensor 72, and the third temperature regulator 74 is detected. The result or measurement result is output to the drive control unit 90 and the control unit 80.

  Here, feedback control for setting the temperature of ink or the like to the set temperature is executed by the drive control unit 90. The drive control unit 90 acquires the detected temperature from the first temperature sensor 34, and the first temperature adjuster 36 so that the detected temperature of the first temperature sensor 34 becomes the set temperature according to the temperature set by the control unit 80. Is controlled. Similarly, the drive control unit 90 drives and controls the second temperature regulator 54 so that the temperature detected by the second temperature sensor 53 becomes the set temperature. Similarly, the third temperature regulator 74 is driven and controlled so that the temperature detected by the third temperature sensor 72 becomes the set temperature.

<Infrared absorber concentration adjustment processing>
Next, the “infrared absorber concentration adjustment process” will be described. Here, “the concentration of the infrared absorbent” is the concentration of the infrared absorbent in the ink after ejection from the recording head. For example, it is the density | concentration of the infrared absorber in the ink droplet discharged on the recording medium from the recording head. In this embodiment, by forming an image using an ink containing an infrared absorber, the absorption efficiency of the laser beam when drying the ink droplet by irradiating the laser beam is improved.

  As described above, in the present embodiment, the ink containing the infrared absorbent is stored while being cooled, and the ink is heated immediately before being supplied to the recording head, thereby suppressing the deterioration of the infrared absorbent. Yes. However, it is difficult to completely eliminate the deterioration of the infrared absorber. When the infrared absorber is deteriorated, the ink droplets are not sufficiently dried due to a decrease in the absorption efficiency of the laser beam. For this reason, there is a possibility that “smudge” in which the ink on the recording medium rubs, “offset” in which the ink adheres to another recording medium, or the like. Therefore, the “infrared absorber concentration adjustment process” is controlled so that the concentration of the infrared absorber in the ink droplets ejected from the recording head is maintained at a predetermined threshold value or more.

  FIG. 4 is a flowchart showing an example of a processing procedure of “infrared absorber concentration adjustment processing” executed in the first embodiment of the present invention. The “infrared absorber concentration adjustment process” is executed by the CPU 80A of the control unit 80 when the ink jet recording apparatus 10 is started up or inspected, or during image formation. In the present embodiment, “infrared absorber concentration adjustment processing” is started in response to an execution instruction from the user via the operation display unit 87.

  First, in step 100, the recording head 12 is driven via the head driving unit 82 on the continuous paper P based on image information of an infrared absorber concentration adjustment image (hereinafter referred to as “adjustment image”). An adjustment image is formed. Next, in step 102, the laser drying device 14 is driven via the laser driving unit 84, the continuous paper P on which the adjustment image is formed is irradiated with laser light, and the image ink formed on the continuous paper P is printed. Dry the drops.

  Next, in step 104, the image temperature measured by the image temperature sensor 16 is acquired. Here, “the concentration of the infrared absorbent” is the concentration of the infrared absorbent in the ink droplets of the mixed liquid ejected from the recording head 12 onto the continuous paper P. The higher the concentration of the infrared absorber in the mixed solution, the higher the laser beam absorption efficiency and the higher the image temperature.

  Next, in step 106, it is determined whether the image temperature acquired in step 104 is less than a set value. The relationship between the image temperature and the concentration of the infrared absorbent is acquired in advance, and the image temperature when the concentration of the infrared absorbent becomes a threshold value (target value) is set as a set value. That is, in step 106, it is determined whether or not the concentration of the infrared absorber is less than a threshold value. When the image temperature is lower than the set value, that is, when the concentration of the infrared absorbent is lower than the threshold value, the process proceeds to step 108. On the other hand, if the image temperature is equal to or higher than the set value, that is, if the concentration of the infrared absorber is equal to or higher than the threshold value, the routine is terminated because there is no need to adjust.

  Note that the threshold value of the concentration of the infrared absorbent may be set according to the type of recording medium, moisture content, reflectance, glossiness, and the like. In the case of continuous paper, the target value may be changed at the end of unwinding or winding. In addition, the threshold value of the concentration of the infrared absorbent may be set according to the type of ink, such as white ink, special color ink, or general-purpose ink.

  In step 108, the concentration of the infrared absorber in the ink droplet is calculated based on the relationship between the image temperature and the concentration of the infrared absorber. When the image temperature is lower than the set value, the concentration of the infrared absorber is also decreased from the threshold concentration. The cause of the decrease in the concentration of the infrared absorber is presumed to be insufficient temperature adjustment of the ink. Therefore, in the next step 110, at least one of the set temperature (cooling temperature) of the first temperature regulator 36 and the set temperature (heating temperature) of the second temperature regulator 54 is changed so as to lower the temperature of the ink. To complete the routine.

  For example, when the degree of decrease in the concentration of the infrared absorber is small, only one of the cooling temperature and the heating temperature is decreased. The set temperature of the first temperature regulator 36 is lowered (for example, 10 ° C. → 8 ° C.) or the set temperature of the second temperature regulator 54 is lowered (for example, 30 ° C. → 28 ° C.). Moreover, when the degree of concentration reduction of the infrared absorbent is large, both the cooling temperature and the heating temperature are reduced. It should be noted that the degree of density decrease may be determined by comparing a reference value with a reference value for a change amount from the threshold concentration in advance.

  When the degree of decrease in the concentration of the infrared absorber is large, control is further performed so that the energy applied to the ink is reduced. For example, the amount of liquid in the second container 50 may be reduced so that the time during which the ink is heated in the second container 50 (that is, the residence time) is shortened. When the residence time in the second container 50 is shortened, the energy applied to the ink is reduced.

  Also, instead of changing the amount of liquid in the second container 50, both set temperatures are changed so that the ink is heated by the third temperature regulator 74 provided in the supply pipe 68, and the second temperature is changed. The time during which the ink is heated in the container 50 (that is, the residence time) may be shortened. In this case, for example, the set temperature of the second temperature regulator 54 is set to room temperature (for example, 25 ° C.), and the set temperature of the third temperature regulator 74 is set to the second temperature (for example, 30 ° C.). Furthermore, a part of the ink in the second container 50 may be discharged, and the amount of ink supplied from the first container 30 may be increased. An infrared absorbent dispersion may be separately added to the discharged ink, and the ink may be readjusted to a composition suitable for ejection.

  Each of the first temperature adjuster 36, the second temperature adjuster 54, and the third temperature adjuster 74 is driven by the drive control unit 90 according to the set temperature after the change, and the ink temperature adjustment is appropriate. The concentration of the infrared absorber converges to the target value.

  In the present embodiment, when the image temperature measured by the image temperature sensor 16 becomes less than the set value, the set temperature of the temperature adjuster for adjusting the temperature of the ink is reset. Thereby, the density | concentration of the infrared absorber in the ink droplet discharged on the continuous paper P from the recording head 12 is maintained more than a predetermined threshold value.

<Modification>
Note that the configuration of the droplet discharge device described in the above embodiment is merely an example, and it goes without saying that the configuration may be changed without departing from the gist of the present invention.

  In the above embodiment, the ink jet recording apparatus has been described as an example of the liquid droplet ejecting apparatus. However, the liquid droplet ejecting apparatus is not limited to the ink jet recording apparatus. As a droplet discharge device, for example, a color filter manufacturing device for manufacturing a color filter by discharging ink or the like on a film or glass, a device for forming an EL display panel by discharging an organic EL solution onto a substrate, a dissolved state A device for forming a bump for mounting components by discharging a solder on a substrate, a device for forming a wiring pattern by discharging a liquid containing metal, and various film forming devices for forming a film by discharging a droplet It may be present as long as it ejects droplets.

  In the above embodiment, the relationship between the image temperature and the concentration of the infrared absorber has been described as not changing.However, when the relationship changes due to the deterioration of the ink absorber due to the deterioration of the infrared absorber, The cooling means and the heating means may be controlled so that the image temperature becomes the target value. If the relationship between the image temperature and the concentration of the infrared absorber changes, the image temperature may not reach the target temperature even if the concentration of the infrared absorber is the target concentration.

  For example, the concentration of the infrared absorbent in the ink corresponding to the measured image temperature is obtained from the relationship between the initial image temperature and the concentration of the infrared absorbent. Further, from the estimated relationship between the image temperature after deterioration and the concentration of the infrared absorber, the concentration (convergent concentration) of the infrared absorber that makes the image temperature the target temperature is obtained. Actually, since it is difficult to accurately estimate the relationship after deterioration, it is assumed that the correction amount ΔT of the image temperature and the correction amount ΔC of the concentration of the infrared absorber are in a substantially proportional relationship. When feedback control (correction, ie, temperature setting change) is repeatedly performed so that the amount ΔT approaches zero, the infrared absorber concentration correction amount ΔC also approaches zero, the image temperature reaches the target temperature, and the infrared ray The concentration of the absorbent converges to the convergent concentration.

DESCRIPTION OF SYMBOLS 10 Inkjet recording device 12 Recording head 14 Laser drying device 16 Image temperature sensor 18 Image density sensor 20 Paper feed roll 22 Winding roll 24 Transport roll 28 Ink supply device 30 First container 32 Ink 34 First temperature sensor 36 First temperature adjustment Vessel 38 first liquid sensor 50 second container 53 second temperature sensor 54 second temperature controller 55 second liquid sensor 56 viscometer 58 stirrer 60 supply pipe 62 first pump 68 supply pipe 70 second pump 72 second 3 temperature sensor 74 3rd temperature regulator 80 control part 82 head drive part 84 laser drive part 86 conveyance drive part 87 operation display part 88 communication part 90 ink supply device drive control part (drive control part)
P Continuous paper

Claims (8)

A droplet discharge head that discharges droplets from a nozzle to form an image on a recording medium;
Storage means for storing a liquid containing an infrared absorber;
Cooling means for cooling the liquid stored in the storage means;
Heating means for heating the liquid supplied from the storage means to the droplet discharge head;
Supply means for supplying the liquid after heating to the droplet discharge head;
Irradiating means for irradiating the image formed on the recording medium with laser light;
A droplet discharge device comprising: A droplet discharge head that discharges droplets from a nozzle to form an image on a recording medium;
First storage means for storing a liquid containing an infrared absorber;
Cooling means for cooling the liquid stored in the first storage means;
A second storage unit having a volume smaller than that of the first storage unit and storing the liquid supplied from the first storage unit to the droplet discharge head;
Heating means for heating the liquid stored in the second storage means;
Supply means for supplying the liquid after heating to the droplet discharge head;
Irradiating means for irradiating the image formed on the recording medium with laser light;
A droplet discharge device comprising:   The droplet discharge device according to claim 1, wherein the cooling unit cools the liquid to a temperature equal to or lower than a first temperature at which the infrared absorbent does not deteriorate.   4. The droplet discharge device according to claim 1, wherein the cooling unit cools the liquid to 10 ° C. or lower. 5.   5. The liquid droplet ejection apparatus according to claim 1, wherein the heating unit heats the liquid to a temperature equal to or higher than a second temperature at which the viscosity of the liquid is suitable for ejection. 6.   6. The droplet discharge device according to claim 1, wherein the heating unit heats the liquid to 30 ° C. or more. Acquisition means for acquiring the concentration of the infrared absorbent in the liquid after being discharged from the droplet discharge head;
Control for controlling at least one of the cooling temperature of the liquid by the cooling means and the heating temperature of the liquid by the heating means when the concentration of the infrared absorbent acquired by the acquiring means is less than a predetermined threshold value Means,
The liquid droplet ejection apparatus according to claim 1, further comprising:   The said control means is controlled so that the energy provided to a liquid by the said heating means reduces, when the density | concentration of the infrared absorber acquired by the said acquisition means is less than a predetermined threshold value. Droplet discharge device.

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